Magnifying playback/display

ABSTRACT

An image sensing apparatus which stores an image signal from an image sensing element and reads out and processes the stored image signal to magnify and display an image on a display device includes a designation unit that designates the magnification ratio of the image to be displayed, a storage unit that stores the magnification ratio designated by the designation unit, and a magnifying processing unit that executes magnifying processing for the stored image signal on the basis of the magnification ratio stored in the storage unit and outputs the image signal to the display device. The magnification ratio stored in the storage unit is updated when a different magnification ratio is designated by the designation unit, and the magnification ratio stored in the storage unit is used for a plurality of images that are sequentially displayed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 10/787,655,filed Feb. 25, 2004, the entire disclosure of which is herebyincorporated by reference.

FIELD OF THE INVENTION

The present invention relates to an image sensing apparatus such as adigital camera which has an image display device and, more particularly,to a magnifying playback/display technique for an image display device.

BACKGROUND OF THE INVENTION

In digital cameras, conventionally, an image sensed by using an imagesensing element is converted into image data and recorded in theinternal memory of the digital camera or on a recording medium such as adetachable memory card. Many of such digital cameras have displaydevices such as a liquid crystal monitor, and obtained image data can bedisplayed on the display device so that the user can confirm the sensedimage.

A display/playback device such as a liquid crystal monitor used in adigital camera is small and simple and therefore cannot display allpixels of the sensed image. To display an image, the number of pixels isreduced by, e.g., thinning them. Although the composition of an objectcan be confirmed even on such a small and simple display/playbackdevice, precise conditions such as the focus state of an image cannot beconfirmed. For this purpose, a digital camera having a function ofmagnifying and playing back part of an image has been proposed.

The magnifying playback/display function will be described below withreference to the accompanying drawings.

The magnifying playback/display function causes a playback imageselector to select an image to be played back and magnifies and playsback the selected image. In a sensed image shown in FIG. 11A, thecentral region of the screen is magnified first by the magnifyingplayback/display function. The magnified portion for the image shown inFIG. 11A corresponds to, e.g., the rectangular frame portion at thecenter in FIG. 12A. The frame size changes depending on themagnification ratio. More specifically, when the magnification ratio ishigh, the frame size decreases to magnify a smaller region. When themagnification ratio is low, the frame becomes large to magnify a widerregion. FIG. 13A shows only the portion inside the rectangular frame inFIG. 12A. This image is magnified in the magnifying playback/displaymode and displayed on an external display device of the digital camera.

To magnify and confirm another portion of the image, the magnifyingplayback region is changed by using a position selection unit, therebyobtaining a necessary image. An example will be described below, inwhich the photographer wants to confirm the shot state of the head partof a person as an object in the image shown in FIG. 11A and changes themagnified region.

FIG. 13B shows an image which is obtained when the magnified region ismoved upward by several steps from the state shown in FIG. 13A in orderto confirm the upper portion of the current image. The magnified regioncorresponding to the image shown in FIG. 13B in the image shown in FIG.11A is indicated by a rectangular frame in FIG. 12B. Since the left handof the person can be recognized in FIG. 13B, the user can know that thehead part of the object is present on the left side of the part shown inFIG. 13B. FIG. 13C shows an image which is obtained by moving themagnified region to the left from the state shown in FIG. 13B. Themagnified region corresponding to the image shown in FIG. 13C in theimage shown in FIG. 11A is indicated by a rectangular frame in FIG. 12C.FIG. 13C shows the head part of the person as the object, though thehead part is not wholly displayed. FIG. 13D shows an image which isobtained when the magnified region is moved upward from the state shownin FIG. 13C in order to display the entire head part. The magnifiedregion corresponding to the image shown in FIG. 13D in the image shownin FIG. 11A is indicated by a rectangular frame in FIG. 12D. In thisway, the magnifying/playback position can be changed to thephotographer's desired position. Hence, the image can be confirmed evenon the small and simple display/playback device.

However, this method is cumbersome for magnifying and playing back aplurality of images.

To magnify and playing back another image different from the image thatis currently being played back, the magnifying playback of the currentmagnified image is ended, and then, another image is selected by theimage selector. After that, the magnifying playback mode must be set tomagnify the central portion of the image and move the magnified regionto a desired position.

Photographer's desired magnifying playback portions are not alwayspresent at the center and tend to concentrate at his/her favoriteposition. Further, in a series of images taken in a continuous shootingmode, the region to be magnified and confirmed is often present at thesame position.

For example, FIG. 11B shows an image that is sensed next to the imageshown in FIG. 11A in the continuous shooting mode. When magnifying isdone in accordance with the conventional procedures, the image shown inFIG. 14A is displayed first. However, the image shown in FIG. 14B is thephotographer's desired magnified image. The rectangular frames shown inFIG. 15 indicate the relationship between FIGS. 14A and 14B in the imageshown in FIG. 11B. As is apparent from FIG. 15, the magnified regionsshown in FIGS. 13D and 14B in the original images are at the sameposition. However, to obtain the magnified image shown in FIG. 14B, thesame magnified region change operation as that executed in obtaining theimage shown in FIG. 13D for the image shown in FIG. 11A must be executedagain.

Some digital cameras display a sensed image for a short time right aftersensing the image (this function is referred to as “REC review”hereinafter) so that the photographer can confirm the sensed imageimmediately after sensing. When the image is magnified during the RECreview, details of the image can be confirmed even in the REC reviewmode. However, when a series of photographs are taken by continuousshooting and almost the same regions in the series of images should bemagnified and confirmed in the REC review mode, the above operation mustbe repeated, i.e., a the central region is magnified for each image, andthe magnified region must be moved from the central portion to thedesired region.

Since this operation is cumbersome, and it requires considerable time toconfirm images, the user may lose the next shutter chance.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the abovesituation, and has as its object to increase the operability inmagnifying playback on the display device of a digital camera.

According to the present invention, the foregoing object is attained byproviding an image sensing apparatus which stores an image signal froman image sensing element and reads out and processes the stored imagesignal to magnify and display an image on a display device, comprising:a designation unit that designates a magnification ratio of the image tobe displayed; a storage unit that stores the magnification ratiodesignated by the designation unit; and a magnifying processing unitthat executes magnifying processing for the stored image signal on thebasis of the magnification ratio stored in the storage unit and outputsthe image signal to the display device, wherein the magnification ratiostored in the storage unit is updated when a different magnificationratio is designated by the designation unit, and the magnification ratiostored in the storage unit is used for a plurality of images that aresequentially displayed.

According to the present invention, the foregoing object is alsoattained by providing a playback method which stores an image signalfrom an image sensing element and reads out and processes the storedimage signal to magnify and display an image on a display device,comprising: designating a magnification ratio of the image to bedisplayed; storing the designated magnification ratio; and executingmagnifying processing for the stored image signal on the basis of themagnification ratio stored in the storage step and outputting the imagesignal to the display device, wherein the stored magnification ratio isupdated when a different magnification ratio is designated in thedesignating step, and the stored magnification ratio is used for aplurality of images that are sequentially displayed.

Other features and advantages of the present invention will be apparentfrom the following description taken in conjunction with theaccompanying drawings, in which like reference characters designate thesame or similar parts throughout the figures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention and,together with the description, serve to explain the principles of theinvention.

FIG. 1 is a block diagram showing the overall arrangement of a digitalcamera according to first and second embodiments of the presentinvention;

FIG. 2A is a plan view showing the outer appearance of the digitalcamera according to the first and second embodiments of the presentinvention;

FIG. 2B is a rear view showing the outer appearance of the digitalcamera according to the first and second embodiments of the presentinvention;

FIG. 3 is a flow chart showing image playback processing according tothe first embodiment of the present invention;

FIG. 4 is a flow chart showing magnifying playback processing accordingto the first embodiment of the present invention;

FIGS. 5A to 5D are views showing a series of images taken in acontinuous shooting mode according to the first embodiment of thepresent invention;

FIGS. 6A to 6E are views showing examples of the magnified images ofFIGS. 5A to 5D;

FIGS. 7A to 7D are views showing the positional relationship between thecontinuously taken images and magnified regions according to the firstembodiment of the present invention;

FIG. 8 is a view showing another image according to the first embodimentof the present invention;

FIG. 9 is a view showing an example of the magnified image of the imageshown in FIG. 8;

FIG. 10 is a flow chart showing image playback processing according tothe second embodiment of the present invention;

FIGS. 11A and 11B are views for explaining conventional image magnifyingprocessing;

FIGS. 12A to 12D are views showing the positional relationship betweenthe image shown in FIG. 11A and magnified regions;

FIGS. 13A to 13D are views showing examples of the magnified images ofthe image shown in FIG. 11A;

FIGS. 14A and 14B are views showing examples of the magnified images ofthe image shown in FIG. 11B; and

FIG. 15 is a view showing the positional relationship between the imageshown in FIG. 11B and magnified regions when the magnified region ischanged in the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described indetail in accordance with the accompanying drawings. The sizes, shapes,and relative layout of constituent elements exemplified in theembodiments should appropriately be changed in accordance with thearrangement and conditions of the apparatus to which the presentinvention is applied. The present invention is not limited to theseillustrative embodiments.

<First Embodiment>

FIG. 1 is a block diagram showing the overall arrangement of a digitalcamera according to the first embodiment of the present invention. Thearrangements and operations of the respective elements will be describedwith reference to FIG. 1.

Light L from an object is received by an image sensing element 13through an image sensing lens 11 and stop 12. The image sensing element13 is an element that converts received light into an electrical signaland is constituted by a solid-state image sensing element such as a CCD(charge-coupled device) and CMOS device. A preprocessing circuit 14 hasa correlated double sampling (CDS) circuit that removes output noise ofthe image sensing element 13 and a nonlinear amplification circuit thatexecutes nonlinear amplification before A/D conversion. An A/D converter15 converts the analog output from the preprocessing circuit 14 into adigital signal. The converted digital image signal is transferred to animage processing circuit 16, undergoes image processing such as contourcompensation, gamma correction, and white balance correction, and isoutput to a memory control circuit 17.

The memory control circuit 17 causes an external storage device 19 suchas a memory card to store, through an interface circuit 18, the imagesignal generated by the image processing circuit 16. An internal storagedevice 20 is a storage device which stores the above-described whitebalance correction value and the like.

The stop 12 is controlled by a control device 21 on the basis of theoutput from a photometry sensor 22 that measures the brightness of theobject. A distance measurement sensor 23 is formed from a line sensorsuch as a known CCD or CMOS and arranged so as to sense the distancemeasurement point of the image sensing element 13. The distancemeasurement sensor 23 outputs, to the control device 21, a defocusedamount signal corresponding to the distance to the object. On the basisof various input signals described above, the control device 21calculates the exposure value and decides the shutter speed andF-number, thereby controlling operation of a shutter device 24.

A first external display device 25 is a liquid crystal display thatdisplays various kinds of setting information mainly related to exposurecontrol. A second external display device 26 is a liquid crystal displaythat displays various kinds of setting information mainly related toimage processing. A third external display device 27 is a color liquidcrystal display which can play back a sensed image and displayinformation related to the sensed image, which is obtained from theimage sensing element 13, and various detailed setting states of thedigital camera.

Reference numeral 31 a denotes an image sensing preparation switch 31 a(SW1); and 31 b, an image sensing designation switch (SW2). Referencenumeral 32 denotes a first information input unit for inputting variouskinds of image sensing setting information, and, in an normal playbackmode, for selecting an image to be played back, and, in a magnifyingplayback mode, for setting the horizontal position in selecting aposition; and 33, a second information input unit for inputting variouskinds of image sensing setting information, and, in the normal playbackmode, for selecting an image to be played back, and, in the magnifyingplayback mode, for setting the vertical position in selecting aposition; and 34, 35 and 36, mode setting units for selecting varioussensing setting modes. Specifically, reference numeral 34 denotes animage sensing mode selection button; 35, AF mode selection button; and36, photometry mode selection button.

Digital system setting selection units 37 to 43 are used for varioussettings and selections related to image processing mainly correspondingto the second external display device 26 and third external displaydevice 27. Specifically, reference numeral 37 denotes a print button;38, a menu button which is pressed to make a set menu of the digitalcamera displayed on the third external display device 27; 39, aselection button which is used to perform various selections when theset menu of the digital camera is displayed in response to the pressingthe menu button 38 and to select an image in the normal image playbackmode or magnifying playback mode; 40, a position setting button which isused together with the first information input unit 32 and secondinformation input unit 33 to select the position of an image to bemagnified; 41, a playback button for initiating playback of a sensedimage in response to the depression of the play back button 41; 42, animage erase button; and 43, a white balance setting button.

A magnifying playback button 44 is used to set the magnifying playbackmode. During the magnifying playback mode, the magnifying playbackbutton 44 also serves to designate an increase in magnification ratio. Amagnification ratio down button 45 is used to input designation fordecreasing the magnification ratio during magnifying playback. When ahome position button 46 is pressed during magnifying playback, themagnifying playback region returns to the image center.

FIG. 2A is a plan view and FIG. 2B is a rear view of the digital cameraaccording to the first embodiment. The same reference numerals as inFIG. 1 denote the same components in FIGS. 2A and 2B, and a detaileddescription thereof will be omitted.

As shown in FIG. 2A, the first external display device 25 is arranged onthe upper surface of the digital camera main body. As shown in FIG. 2B,the second external display device 26 is arranged on the rear surface ofthe digital camera main body. The third external display device 27 isarranged on the rear surface of the digital camera main body, i.e.,almost on the same surface as the second external display device 26, asshown in FIG. 2B.

Reference numeral 31 denotes a release button. The image sensingpreparation switch (SW1) 31 a is turned on at the first stroke position(e.g., half stroke) of the release button 31. The image sensingdesignation switch (SW2) 31 b is turned on at the second stroke position(e.g., full stroke) of the release button 31. Each of the firstinformation input unit 32 and second information input unit 33 isconstituted by a rotary dial input operation member.

The digital system setting selection units 37 to 43 are arranged on therear surface of the digital camera main body, i.e., almost on the samesurface as the second external display device 26, as shown in FIG. 2B.

An image playback operation of the digital camera according to the firstembodiment having the above arrangement will be described next withreference to the flow chart shown in FIG. 3.

Given that image sensing operations have been performed, and image datais already written in the external storage device 19. When the playbackbutton 41 is pressed in this state, the image playback mode starts. Aunique number (referred to as “image number” hereinafter) isautomatically assigned to each image by the digital camera at the timeof image sensing.

When the image playback mode starts, a timer t is cleared and thenstarted to count time in step S101. The timer t is a counter formeasuring the time until display on the third external display device 27is turned off. Although a detailed description of the operation isomitted here, the user can arbitrarily select the time until the thirdexternal display device 27 is turned off.

In step S102, the control device 21 reads out, from the internal storagedevice 20, the image number of an image to be played back. In step S103,data corresponding to the image number acquired in step S102 is loadedfrom the external storage device 19 to the internal storage device 20and converted into data displayable within the display range of thethird external display device 27. In step S104, the image data loaded tothe internal storage device 20 is arithmetically processed, and thethird external display device 27 is caused to display the image.

Unless a button operation in step S105 or S106 is performed, or aplayback stop designation is input in step S107 (the operations will bedescribed later), the displayed image is continuously displayed untilthe timer t exceeds T1 in step S108. In step S111, the value of thetimer t is incremented by one. When the value of the timer tcontinuously increases and exceeds T1 in step S108, the flow advances tostep S109 to turn off the third external display device 27, thus endingthe image playback processing.

If the selection button 39 is pressed in step S105, an image selectionstate is set, and the flow advances to step S112. In step S112, thenumber of the displayed image is changed in response to operation of thefirst information input unit 32 or second information input unit 33. Forexample, when the first information input unit 32 or second informationinput unit 33 is rotated clockwise, the image number increases. When theunit 32 or 33 is rotated counterclockwise, the image number decreases.

When the image number is decided in step S112, the decided image numberis stored in the internal storage device 20 in step S113, and the flowreturns to step S101. The image having the selected image number isdisplayed on the third external display device 27 by the above-describedprocessing in steps S101 to S104.

When the magnifying playback button 44 is pressed (YES in step S106),the flow advances to step S114 to execute magnifying playbackprocessing. The magnifying playback processing will be described laterin detail with reference to FIG. 4.

When an image playback stop designation is input in step S107, the flowadvances to step S109 to turn off the third external display device 27,thus ending the image playback processing. The image playback stop isexecuted, for example, when an operation except the image playback modeis designated by the menu button 38 or various selection buttons, or theimage sensing preparation switch (SW1) 31 a is pressed to immediatelyset the image sensing preparation state.

The magnifying playback processing will be described next with referenceto FIG. 4.

In step S121, the timer t is cleared and then started to count time.

Since the image number to be displayed is already decided before stepS106 in FIG. 3, the control device 21 loads the image data from theexternal storage device 19 to the internal storage device 20 in stepS122. The image data is converted into data displayable within thedisplay range of the third external display device 27.

In step S123, the control device 21 acquires the magnification ratio andthe central position (magnifying center position) of the magnificationregion from the internal storage device 20 to decide the range to bedisplayed on the third external display device.

In step S124, an image that is magnified on the basis of themagnification ratio and magnifying center position acquired in step S123is displayed on the third external display device 27.

Unless a button is pressed during processing in steps S125 to S130, or amagnifying playback stop designation is input in step S131 (theoperations will be described later), the magnified image is continuouslydisplayed until the timer t exceeds T1 in step S132. If the timer t doesnot exceed T1, the value of the timer t is incremented by one in stepS134. The value T1 to be compared with the timer t may have either thesame value as that used for comparison in step S108 in FIG. 3 or adifferent value. When the value of the timer t continuously increases instep S134 and exceeds T1 in step S132, the flow advances to step S133 toturn off the third external display device 27, thus ending the imageplayback processing.

Operations executed when any of the buttons is pressed in any of stepsS125 to S130 will be described next.

When the magnifying playback button 44 is pressed in step S125, the flowadvances to step S135 to raise the current magnification ratio by onestep. In step S140, the raised magnification ratio is stored in theinternal storage device 20. Then, the flow returns to step S121.

When the magnification ratio down button 45 is pressed in step S126, theflow advances to step S136 to reduce the current magnification ratio byone step. In step S140, the reduced magnification ratio is stored in theinternal storage device 20.

When the position setting button 40 is pressed in step S127, amagnification region selection operation starts. In step S137,calculation for selecting the position of the magnification region inthe image is executed in accordance with the rotational amount of thefirst information input unit 32 and second information input unit 33.When the first information input unit 32 is rotated clockwise, the valueof the magnifying center position that indicates a region on the rightside of the currently magnified and displayed region is calculated. Whenthe first information input unit 32 is rotated counterclockwise, thevalue of the magnifying center position that indicates a region on theleft side of the currently magnified and displayed region is calculated.

When the second information input unit 33 is rotated clockwise, thevalue of the magnifying center position that indicates a region on thelower side of the currently magnified and displayed region iscalculated. When the second information input unit 33 is rotatedcounterclockwise, the value of the magnifying center position thatindicates a region on the upper side of the currently magnified anddisplayed region is calculated. The magnifying center position of themagnified image, which is obtained as a result of the calculation, isstored in the internal storage device 20 in step S141, then the flowreturns to step S121. The moving directions by the operations of thefirst information input unit 32 and second information input unit 33 arenot limited to those described above and can appropriately be designed.In the above-described example, the magnifying center position of themagnification region is calculated. However, if the magnification regionis rectangular, the position of any corner may be calculated and stored.

When the home position button 46 is pressed in step S128, themagnification region returns to a preset region. If default setting hasbeen done at the time of shipment from the factory to display, e.g., thecentral portion of the screen, calculation is executed to obtain theposition of the central portion of the image. In step S141, the obtainedposition is stored in the internal storage device 20 as the magnifyingcenter position, then the flow returns to step S121.

When the selection button 39 is pressed in step S129, an image selectionoperation is executed. In step S139, when the first information inputunit 32 is operated, the image number of the image to be displayed ischanged. When the first information input unit 32 is rotated clockwise,the image number increases. When the first information input unit 32 isrotated counterclockwise, the image number decreases. In step S142, theimage number decided in step S139 is stored in the internal storagedevice 20, then the flow returns to step 121.

When any change is done in step S140, S141, or S142, and the flowreturns to step S121, a magnified image corresponding to the changedcontents is displayed on the third external display device 27 by theprocessing in steps S121 to S124.

It should be noted that in the above explanation, when the positionsetting button 40 or selection button 39 is pressed in step S127 orS129, the dial operation of the first information input unit 32 and/orsecond information input unit 33 is always performed in step S137 orS139. However, the digital camera has a function of, e.g., restoring thestate before pressing of the button (i.e., the flow returns to stepS125) if the dial operation is not performed for a predetermined time.For this reason, the processing does not indefinitely wait for theoperation of the first information input unit 32 or second informationinput unit 33 in step S137 or S139.

When the playback button 41 is pressed in step S130, the magnifyingplayback processing is ended, and the flow returns to step S101 in FIG.3 to perform the normal playback operation. In this case, the entireimage having the same image number as that of the magnified image isdisplayed.

When designation for interrupting the magnifying playback operation isinput in step S131 by the same processing as described in step S107 inFIG. 3, the flow advances to step S133. In step S133, the third externaldisplay device 27 is turned off, and thus the image playback processingincluding the magnifying playback processing is ended.

A display example will be described next in detail, in which afterimages are sensed by the digital camera of the present invention in thecontinuous shooting mode wherein images are taken successively at apredetermined interval, the images are confirmed on the basis of theabove-described image playback processing and magnifying playbackprocessing.

FIGS. 5A to 5D are views showing four images sensed in the continuousshooting mode of the digital camera of the present invention. Asdescribed above, an image number is automatically assigned to each imageby the digital camera at the time of image sensing. It is assumed thatimage numbers 201 to 204 are assigned to the images shown in FIGS. 5A to5D.

When the user wants magnifying playback of a desired region of the imageshown in FIG. 5A after sensing the image, he/she operates the selectionbutton 39 and first information input unit 32 first to play back theimage having the image number 201 (step S104). When the magnifyingplayback button 44 is pressed during playback of the image, themagnifying playback processing starts (step S114). The magnificationratio and magnifying center position are set by the operations in stepS125 to S127 in FIG. 4 to magnify and display the desired portion of theimage.

FIG. 6A shows an example of a magnified image desired by the user, whichis displayed as a result of the magnifying operation for the image shownin FIG. 5A. The magnified region in the image shown in FIG. 5A at thistime is indicated by a rectangular frame in FIG. 7A. The operation untilthe image shown in FIG. 6A is obtained is the same as that describedwith reference to FIGS. 12A to 13D.

To display the next image 202 (FIG. 5B) from the state in which themagnified image of FIG. 6A is displayed, the selection button 39 ispressed (step S129), and the first information input unit 32 is rotatedclockwise (step S139). On the basis of information from the firstinformation input unit 32, the control device 21 calculates that theimage number increases from 201 to 202 and stores the image number 202in the internal storage device 20 (step S142).

To update the time until display OFF, the timer t is reset and restarted(step S121). Image data with the image number 202 is loaded from theexternal storage device 19 to the internal storage device 20 (stepS122).

Next, the control device 21 acquires, from the internal storage device20, the magnification ratio and position information of the magnifiedimage which are stored in advance (step S123). The magnified image isgenerated from the image data with the image number 202, and thus themagnified image of the same magnification ratio at the same position asthose of the image with the image number 201 is displayed on the thirdexternal display device 27 (step S124).

FIG. 6B shows the image displayed at this time. The magnified regioncorresponding to the image shown in FIG. 6B in the image shown in FIG.5B is indicated by a rectangular frame in FIG. 7B. When the image isdisplayed on the basis of the same magnification ratio and magnifyingcenter position as those of the image with the image number 201 in theabove-described way, the magnified image desired by the user can beobtained in this case.

When the user presses the selection button 39 and rotates the firstinformation input unit 32 clockwise to see the next magnified image withthe image number 203 (FIG. 5C), the magnified image shown in FIG. 6C isdisplayed. The magnified region corresponding to the image shown in FIG.6C in the image shown in FIG. 5C is indicated by rectangular frame 1 inFIG. 7C. If the magnified image desired by the photographer is in theregion surrounded by rectangular frame 2 in FIG. 7C, the image shown inFIG. 6D can be obtained by slightly moving the magnification region tothe right and upper sides.

When the photographer presses the selection button 39 and rotates thefirst information input unit 32 clockwise to see the next magnifiedimage with the image number 204 (FIG. 5D), the image shown in FIG. 6E isdisplayed. The magnified region corresponding to the image in FIG. 6E inthe image shown in FIG. 5D is indicated by a rectangular frame in FIG.7D.

As described above, the position where the user wants to confirm theseries of images sensed in the continuous shooting mode does not changesso greatly. In the digital camera according to the first embodiment,since magnifying playback of an image is executed at the same region asthat of the precedingly magnified and displayed image, the images can beconfirmed easily and quickly.

The region to be magnified in an image sometimes largely changes inaccordance with a change of the sensing scene. For example, assume thatan image shown in FIG. 8 has an image number 205 next to the image withthe image number 204 shown in FIG. 5D, and the central portion of theimage is the region to be magnified desired by the user. In this case,the central portion of the image can quickly be magnified and displayedby pressing the home position button 46 (step S128). FIG. 9 shows themagnified image of the central portion of the image shown in FIG. 8.

A user's favorite position can be registered as the home position towhich the magnification region is moved in response to the operation ofthe home position button 46. Some users have compositions to their owntastes and therefore a predetermined position to be confirmed by themagnifying playback function. When each user registers his/her favoriteposition as the home position, favorite portion can be magnified andplayed back by pressing the home position button 46 during magnifyingplayback processing.

The first embodiment has been described by using the continuous shootingmode to help understanding the arrangement of the present invention.However, the present invention is not limited to this. Even in singleimage shooting without using the continuous shooting mode, the point tobe magnified is often almost the same throughout the images because of,e.g., the user's taste in composition. Hence, the magnifying playbackfunction of the digital camera of the present invention can effectivelybe used.

<Second Embodiment>

The second embodiment of the present invention will be described next.The arrangement of a digital camera according to the second embodimentis the same as that shown in FIGS. 1, 2A, and 2B described in the firstembodiment.

Some conventional digital cameras have a function of, after sensing inthe continuous shooting mode, automatically sequentially displayingimages in the time-series, i.e., chronological order. This function isalso called a “continuous shooting slide show mode”. Since thecontinuously sensed images can sequentially be confirmed in thetime-series order in this mode, the correlation between the series ofimages along the time axis can also be checked. In the secondembodiment, a magnifying playback operation in the continuous shootingslide show mode will be described.

FIG. 10 is a flow chart showing image playback processing in thecontinuous shooting slide show mode in the digital camera according tothe second embodiment. The same step numbers as in FIG. 4 denote thesame operations in FIG. 10. Operations different from FIG. 4 will mainlybe described. As preconditions, assume that image sensing is executed inadvance in the continuous shooting mode, and image numbers aresequentially assigned to a series of images. In the series of images,the oldest image number and the latest image number are stored in aninternal storage device 20 as Istart and Iend, respectively.

When image playback processing in the continuous shooting slide showmode starts, in step S201, the first image number Istart in thecontinuous shooting mode is read out from the internal storage device 20and set in an image number counter i that counts the image number. Inaddition, a timer t that counts the display time is reset to 0 andstarted.

In step S122, a control device 21 acquires image data on the basis ofthe image number i. In step S123, the magnification ratio and imageposition stored in the internal storage device 20 are acquired. Theimage data is acquired either from an external storage device 19 or fromthe internal storage device 20 like in a REC review mode wherein eachsensed image is displayed for a short time immediately after sensing. Instep S124, the image of the image number i is displayed on a thirdexternal display device 27 on the basis of the magnification ratio andmagnifying center position stored in the internal storage device 20 inadvance. In the second embodiment, a magnification ratio at which anentire image can be displayed on the third external display device 27 isstored as the initial value of the magnification ratio, and the centeris stored as the initial value of the magnifying center position.Operations in steps S125 to S142 are the same as in FIG. 4. If aplayback button 41 is pressed in step S202, the magnification ratio isreturned in step S203 to that for the normal playback size (×1) at whichthe sensed image can be fully displayed. In step S140, the changedmagnification ratio is stored in the internal storage device 20.

If no button operation is executed in steps S125 to S131 or in stepS202, the image displayed in step S124 is continuously displayed untilthe timer t exceeds a preset time T2 in step S132. In step S134, thevalue of the timer t is incremented by one. When the timer t exceeds T2,the flow advances to step S204 to determine whether the image numbercounter i holds the image number Iend which indicates the last imagesensed in the continuous shooting mode. If NO in step S204, the flowadvances to step S205 to display the next image. The value of the imagenumber counter i is incremented by one. In addition, the timer t isreset to 0 and restarted. Then, the flow returns to step S122 to acquirethe image with the next image number and to play back the next image.

When image playback stop designation is input in step S131, or it isdetermined in step S204 that display of the last image in the continuousshooting slide show mode is ended, the third external display device 27is turned off in step S133, thus ending the image playback processing.

A display example will be described next in detail with reference toFIGS. 5A to 7D, in which when images sensed in the continuous shootingmode are sequentially played back and displayed in the continuousshooting slide show mode by the digital camera of the present invention,the images are confirmed on the basis of the above-described imageplayback processing. As in the first embodiment, image numbers 201 to204 are assigned to the images shown in FIGS. 5A to 5D.

When the user detaches his/her hand from a release button 31(particularly, an image sensing designation switch (SW2) 31 b),continuous shooting is ended. The control device 21 starts image displaypreprocessing. In this case, 201 is stored as Istart, and 204 is storedas Iend. When the magnification ratio stored in the internal storagedevice 20 corresponds to full window display, the image shown in FIG. 5Ais displayed in step S124. In the REC review mode, the data of thesensed images still remain in the internal storage device 20, and theyare sequentially stored in the external storage device 19.

After the start of display of the image (the image shown in FIG. 5A) ofthe image number 201, when the user wants magnifying display of adesired region of the image within the time T2, he/she sets themagnification ratio and magnifying center position by the operations instep S125, S126, and S127 in FIG. 10 to magnify and display the desiredpart of the image. In the first embodiment, the third external displaydevice 27 is turned off if no button operation is executed for apredetermined time during display. In the continuous shooting slide showmode, when the time has elapsed, the next image is displayed. FIG. 6Ashows an example of a magnified image desired by the user, which isdisplayed as a result of the operations in steps S125, S126, and S127.The magnified region in the image shown in FIG. 5A at this time isindicated by a rectangular frame in FIG. 7A.

When the time T2 has elapsed while the user confirms the image displayedin the window as shown in FIG. 6A, the flow advances to step S204. Sincethe value of the image number counter i is smaller than Iend, the nextimage is displayed. More specifically, the image number is changed to202 (the image shown in FIG. 5B), the timer t is initialized to 0 (stepS205), and the flow returns to step S122 to start display processing ofthe image of the image number 202.

The image data with the image number 202 is loaded either from theexternal storage device 19, or from the internal storage device 20 inthe REC review mode (step S122).

Next, the control device 21 acquires, from the internal storage device20, the magnification ratio and magnifying center position stored whenthe image of the image number 201 is displayed (step S123). A magnifiedimage is generated from the image of the image number 202. The magnifiedimage having the same magnifying center position and magnification ratioas those of the image with the image number 201 is displayed on thethird external display device 27 (step S124).

FIG. 6B shows the image displayed at this time. The magnified regioncorresponding to the image shown in FIG. 6B in the image shown in FIG.5B is indicated by a rectangular frame in FIG. 7B. When the image isdisplayed on the basis of the same magnification ratio and magnifyingcenter position as those of the image of the image number 201 in theabove-described way, the user can confirm the desired magnified imagewith sufficient time even in the time T2.

When the time T2 has elapsed while the user confirms the image shown inFIG. 6B, the above-described processing is repeated to display the nextimage (FIG. 5C) of the image number 203.

FIG. 6C shows an image displayed at this time. The magnified regioncorresponding to the image shown in FIG. 6C in the image shown in FIG.5C is indicated by a rectangular frame 1 in FIG. 7C. If the imagedesired by the user is in the region surrounded by rectangular frame 2in FIG. 7C, the image shown in FIG. 6D can be obtained by slightlymoving the magnification region to the right and upper sides. Asdescribed above, even in a short time within the time T2, the user canchange the position of the magnified image and confirm the magnifiedimage.

When the time T2 has further elapsed, a magnified image shown in FIG.6E, which has the image number 204, is displayed. The magnified regioncorresponding to the image shown in FIG. 6E in the image shown in FIG.5D is indicated by a rectangular frame in FIG. 7D. The region is thesame as that shown in FIG. 60. Hence, the user can confirm the desiredmagnified image without changing the magnified region.

As described above, the image portion which the user wants to confirm inthe series of images sensed in the continuous shooting mode does notmove so greatly. In the digital camera according to the secondembodiment, since magnifying playback of an image is executed such thatthe same magnification region of the image as that of the precedinglymagnified and displayed image is displayed, the images can be confirmedeasily and quickly.

In the second embodiment, the series of images obtained by continuousshooting are played back in the continuous shooting slide show mode. Inthe REC review mode, by storing the magnification ratio and magnifyingcenter position in, e.g., a nonvolatile storage device after the end ofsensing, the same region as the magnified region precedingly displayedin the REC review mode can be magnified and displayed even in singleimage shooting at different time. In the single image shooting mode, thesame value is held as Istart and Iend. In addition, a mode wherein allimages stored in the external storage device 19 are subjected to theslide show can be implemented by setting Istart for the first storedimage and Iend for the last stored image.

In some cases, a completely different image is sensed immediately aftercontinuous shooting. For example, assume that the image shown in FIG. 8has an image number 205 next to the image shown in FIG. 50. In thiscase, the magnified image of the central portion of the image can bequickly displayed, as shown in FIG. 9, by pressing a home positionbutton 46 as described above in the first embodiment.

<Other Embodiments>

Note that the present invention can be applied to an apparatuscomprising a single device or to system constituted by a plurality ofdevices.

Furthermore, the invention can be implemented by supplying a softwareprogram, which implements the functions of the foregoing embodiments,directly or indirectly to a system or apparatus, reading the suppliedprogram code with a computer of the system or apparatus, and thenexecuting the program code. In this case, so long as the system orapparatus has the functions of the program, the mode of implementationneed not rely upon a program.

Accordingly, since the functions of the present invention areimplemented by computer, the program code installed in the computer alsoimplements the present invention. In other words, the claims of thepresent invention also cover a computer program for the purpose ofimplementing the functions of the present invention.

In this case, so long as the system or apparatus has the functions ofthe program, the program may be executed in any form, such as an objectcode, a program executed by an interpreter, or scrip data supplied to anoperating system.

Example of storage media that can be used for supplying the program area floppy disk, a hard disk, an optical disk, a magneto-optical disk, aCD-ROM, a CD-R, a CD-RW, a magnetic tape, a non-volatile type memorycard, a ROM, and a DVD (DVD-ROM and a DVD-R).

As for the method of supplying the program, a client computer can beconnected to a website on the Internet using a browser of the clientcomputer, and the computer program of the present invention or anautomatically-installable compressed file of the program can bedownloaded to a recording medium such as a hard disk. Further, theprogram of the present invention can be supplied by dividing the programcode constituting the program into a plurality of files and downloadingthe files from different websites. In other words, a WWW (World WideWeb) server that downloads, to multiple users, the program files thatimplement the functions of the present invention by computer is alsocovered by the claims of the present invention.

It is also possible to encrypt and store the program of the presentinvention on a storage medium such as a CD-ROM, distribute the storagemedium to users, allow users who meet certain requirements to downloaddecryption key information from a website via the Internet, and allowthese users to decrypt the encrypted program by using the keyinformation, whereby the program is installed in the user computer.

Besides the cases where the aforementioned functions according to theembodiments are implemented by executing the read program by computer,an operating system or the like running on the computer may perform allor a part of the actual processing so that the functions of theforegoing embodiments can be implemented by this processing.

Furthermore, after the program read from the storage medium is writtento a function expansion board inserted into the computer or to a memoryprovided in a function expansion unit connected to the computer, a CPUor the like mounted on the function expansion board or functionexpansion unit performs all or a part of the actual processing so thatthe functions of the foregoing embodiments can be implemented by thisprocessing.

As many apparently widely different embodiments of the present inventioncan be made without departing from the spirit and scope thereof, it isto be understood that the invention is not limited to the specificembodiments thereof except as defined in the appended claims.

What is claimed is:
 1. An image display apparatus which displays aplurality of images comprising: a position designation unit configuredto, in response to an operation by a user during displaying a firstimage, designate a position of magnification part; a display controlunit configured to magnify a part of the first image on the basis of theposition of the magnification part designated by the positiondesignation unit and to reproduce and display the magnified part of thefirst image on a display unit; and an image changing unit configured tochange the display from the magnified part of the first image to amagnified part of a second image on the display unit duringreproduction, the second image being different from the first image,based on the position of the magnification part designated by theposition designation unit during the first image is displayed.
 2. Theapparatus according to claim 1 further comprising: a displaymagnification designation unit configured to, in response to anoperation by the user during displaying the first image, designate adisplay magnification ratio for magnifying an image; wherein themagnified part of the first image is a magnified image of the firstimage based on the display magnification ratio designated by the displaymagnification designation unit during the first image is displayed andthe position of the magnification part designated by the positiondesignation unit during the first image is displayed, and the magnifiedpart of the second image is a magnified image of a part of the secondimage different from the first image based on the display magnificationratio designated by the display magnification designation unit duringthe first image is displayed and the position of the magnification partdesignated by the position designation unit during the first image isdisplayed.
 3. The apparatus according to claim 1 further comprising anend control unit configured to control to end displaying of an image onthe display unit in a case where a predetermined period of time elapseswithout receiving any of a plurality of inputs including at least aninput from the position designation unit.
 4. The apparatus according toclaim 1 further comprising an image sensing unit.
 5. The apparatusaccording to claim 1, wherein the display control unit executes themagnification in an image playback mode.
 6. The apparatus according toclaim 1, wherein the display control unit executes the magnification ina REC review mode in which a sensed image is displayed for saidpredetermined period of time immediately after sensing the image.
 7. Theapparatus according to claim 1, wherein the display control unitdisplays the plurality of images in a slide show mode in which each of aplurality of pre-recorded images is sequentially magnified, inaccordance with the position of the magnification part designated by theposition designation unit during the first image is displayed, anddisplayed in the display unit for said predetermined period of time. 8.The apparatus according to claim 1, wherein the display control unitexecutes the magnification in a continuous shooting slide show mode inwhich continuously sensed images are sequentially displayed for thepredetermined time for each image immediately after continuous shooting.9. The apparatus according to claim 1, further comprising a returnoperation member, wherein when said return operation member is operatedduring the magnified part of the second image is displayed, a displaycontrol unit changes an image to be displayed from the magnified part ofthe second image to a magnified image of a part of the second imagebased on a preset position.
 10. The apparatus according to claim 1,wherein the image display apparatus is a digital camera.
 11. Theapparatus according to claim 1, wherein the position of magnificationpart to be magnified is allowed to be changed during either of the firstand second images is displayed.
 12. The apparatus according to claim 2,wherein the display magnification designation unit receives from theuser an instruction to increase and an instruction to decrease themagnification ratio of the magnification part designated by the positiondesignation unit.
 13. The apparatus according to claim 2 furthercomprising a storage control unit configured to control to store in astorage unit position information about the position of themagnification part designated by the position designation unit duringdisplaying the first image and magnification ratio information about themagnification ratio designated by the display magnification designationunit during displaying the first image.
 14. The apparatus according toclaim 13 further comprising: an image selection unit configured toselect the second image recorded on a memory, different from the firstimage, to be displayed on the display unit; and an acquisition unitconfigured to acquire from the storage unit the position information andthe magnification ratio information in response to the image selectionunit selecting the second image, wherein the image changing unit changesthe display from the magnified part of the first image to the magnifiedpart of the second image on the display unit based on the positioninformation and the magnification ratio information acquired by theacquisition unit.
 15. The apparatus according to claim 14, wherein theposition information stored in the storage unit is updated when adifferent position is designated by the position designation unit, andthe magnification ratio information stored in the storage unit isupdated when a different magnification ratio is designated by thedisplay magnification designation unit, and the image changing unit usesthe position information and the magnification ratio information storedin the storage unit for a third image to be displayed subsequent to thesecond image.
 16. The apparatus according to claim 1 further comprisinga storage control unit configured to control to store information aboutthe position of the magnification part designated by the positiondesignation unit in a storage unit during displaying the first image.17. The apparatus according to claim 16 further comprising: an imageselection unit configured to select the second image recorded on amemory, different from the first image, to be displayed on the displayunit; and an acquisition unit configured to acquire from the storageunit the information in response to the image selection unit selectingthe second image, wherein the image changing unit changes the displayfrom the magnified part of the first image to the magnified part of thesecond image on the display unit based on the information acquired bythe acquisition unit.
 18. The apparatus according to claim 17, whereinthe information stored in the storage unit is updated when a differentposition is designated by the position designation unit, and the imagechanging unit uses the information stored in the storage unit for athird image to be displayed subsequent to the second image.
 19. Theapparatus according to claim 1, wherein the first image and the secondimage are sensed by a digital camera.
 20. The apparatus according toclaim 1, wherein, if the position of the magnified part of the secondimage is not changed during the second image is displayed, the imagechanging unit changes the display from the magnified part of the secondimage to a magnified part of a third image on the display unit duringreproduction, the third image being different from the first image andthe second image, based on the position of the magnification partdesignated by the position designation unit during the first image isdisplayed.
 21. An image display control method for displaying aplurality of images comprising: a position designation step of, inresponse to an operation by a user during displaying a first image,designating a position of magnification part; a display control step ofmagnifying a part of the first image on the basis of the position of themagnification part designated in the position designation step and toreproduce and display the magnified part of the first image on a displayunit; an image changing step of changing the display from the magnifiedpart of the first image to a magnified part of a second image on thedisplay unit during reproduction, the second image being different fromthe first image, based on the position of the magnification partdesignated in the position designation step during the first image isdisplayed.
 22. The method according to claim 21 further comprising: adisplay magnification designation step of, in response to an operationby the user during displaying the first image, designating a displaymagnification ratio for magnifying an image; wherein the magnified partof the first image is a magnified image of the first image based on thedisplay magnification ratio designated in the display magnificationdesignation step during the first image is displayed and the position ofthe magnification part designated in the position designation stepduring the first image is displayed, and the magnified part of thesecond image is a magnified image of a part of the second imagedifferent from the first image based on the display magnification ratiodesignated in the display magnification designation step during thefirst image is displayed and the position of the magnification partdesignated in the position designation step during the first image isdisplayed.
 23. The method according to claim 21 further comprising anend control step of controlling to end displaying of an image on thedisplay unit in a case where a predetermined period of time elapseswithout receiving any of a plurality of inputs including at least aninput in the position designation step.
 24. The method according toclaim 21, wherein further comprising an image sensing step.
 25. Themethod according to claim 21, wherein the display control step executesthe magnification in an image playback mode.
 26. The method according toclaim 21, wherein the display control step executes the magnification ina REC review mode in which a sensed image is displayed for saidpredetermined period of time immediately after sensing the image. 27.The method according to claim 21, wherein the display control stepdisplays the plurality of images in a slide show mode in which each of aplurality of pre-recorded images is sequentially magnified, inaccordance with the position of the magnification part designated in theposition designation step during the first image is displayed, anddisplayed in the display unit for said predetermined period of time. 28.The method according to claim 21, wherein the display control stepexecutes the magnification in a continuous shooting slide show mode inwhich continuously sensed images are sequentially displayed for thepredetermined time for each image immediately after continuous shooting.29. The method according to claim 21, further comprising a returnoperation step of receiving a return operation from the user, whereinwhen said return operation is received during the magnified part of thesecond image is displayed, a display control step changes an image to bedisplayed from the magnified part of the second image to a magnifiedimage of a part of the second image based on a preset position.
 30. Themethod according to claim 21, wherein the position of magnification partto be magnified is allowed to be changed during either of the first andsecond images is displayed.
 31. The apparatus according to claim 21,wherein the image display control method is executed in a digitalcamera.
 32. The method according to claim 22, wherein the displaymagnification designation step receives from the user an instruction toincrease and an instruction to decrease the magnification ratio of themagnification part designated in the position designation step.
 33. Themethod according to claim 22 further comprising a storage control stepof controlling to store in a storage unit position information about theposition of the magnification part designated in the positiondesignation step during displaying the first image and magnificationratio information about the magnification ratio designated in thedisplay magnification designation step during displaying the firstimage.
 34. The method according to claim 33 further comprising: an imageselection step of selecting the second image recorded on a memory,different from the first image, to be displayed on the display unit; andan acquisition step of acquiring from the storage unit the positioninformation and the magnification ratio information in response to theimage selection step selecting the second image, wherein the imagechanging step changes the display from the magnified part of the firstimage to the magnified part of the second image on the display unitbased on the position information and the magnification ratioinformation acquired in the acquisition step.
 35. The method accordingto claim 34, wherein the position information stored in the storage unitis updated when a different position is designated in the positiondesignation step, and the magnification ratio information stored in thestorage unit is updated when a different magnification ratio isdesignated in the display magnification designation step, and the imagechanging step uses the position information and the magnification ratioinformation stored in the storage unit for a third image to be displayedsubsequent to the second image.
 36. The method according to claim 21further comprising a storage control step of controlling to storeinformation about the position of the magnification part designated inthe position designation step in a storage unit during displaying thefirst image.
 37. The method according to claim 36 further comprising: animage selection step of selecting the second image recorded on a memory,different from the first image, to be displayed on the display unit; andan acquisition step of acquiring from the storage unit the informationin response to the image selection step selecting the second image,wherein the image changing step changes the display from the magnifiedpart of the first image to the magnified part of the second image on thedisplay unit based on the information acquired in the acquisition step.38. The method according to claim 37, wherein the information stored inthe storage unit is updated when a different position is designated inthe position designation step, and the image changing step uses theinformation stored in the storage unit for a third image to be displayedsubsequent to the image.
 39. The method according to claim 21, whereinthe first image and the second image are sensed by a digital camera. 40.The method according to claim 21, wherein, if the position of themagnified part of the second image is not changed during the secondimage is displayed, the image changing step changes the display from themagnified part of the second image to a magnified part of a third imageon the display unit during reproduction, the third image being differentfrom the first image and the second image, based on the position of themagnification part designated in the position designation step duringthe first image is displayed.
 41. A non-transitory readable storagemedium having stored thereon a program which is executable by an imageprocessing apparatus, the program having a program code for realizingthe image display control method according to claim 21.